CAMP/CAMPCS is the largest study of childhood asthma ever conducted, and hence presents a unique opportunity to examine the hypothesis that adherence in this clinical trial is highly variable and mediates the dose-response relationship between treatment and outcomes. Recently analyzed data from the Childhood Asthma Management Program (CAMP) has revealed that average budesonide adherence was 77 percent in the first year but dropped to 55 percent in year four of this multicenter pediatric asthma clinical trial, with the most dramatic drop in adherence occurring among African-American children. The CAMP Continuation Study (CAMPCS) is a 4.5 year observational followup study of 907 children who were enrolled in CAMP, many of whom remain on anti- inflammatory medication. Scheduled for completion on April 30, 2004, the objective of this landmark study is to further understand the role of inflammation and its' treatment in the progression of childhood asthma. This proposal seeks to conduct an ancillary study to CAMPCS which will help achieve this objective. Medication adherence estimations will be used to clarify dose-response relationships in the evaluation of the effect of ongoing anti-inflammatory treatment upon lung function, airway responsiveness, physical growth, respiratory symptoms, health care utilization, lens opacities, and quality of life. The proposed study will evaluate adherence to controller medicine in these children through monthly telephone interviews over a period of six months, which inquire about adherence on the previous day. Adherence assessments based upon short-term recall via telephone interviews by outside personnel have been shown in studies involving other chronic conditions to provide accurate adherence estimates. Our group has recently piloted 24-hour telephone interviews about children's use of asthma medications and found that these results correlated .77 with information obtained with the use of an electronic adherence monitor on the child's metered dose inhaler. The telephone-interview approach is very cost-effective, does not burden staff at the eight CAMPCS sites, and unlike electronic monitors is not limited to a subset of ICS inhalers. In the final telephone interview, participants will be asked a series of questions about their asthma and its' treatment in order to determine whether nonadherence is related to strength of the caregiver-patient relationship, perceived effectiveness of the medication, psychological distress, family support, illness severity, or coping capacity.